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''Buteo'' is a
genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
of medium to fairly large, wide-ranging raptors with a robust body and broad wings. In the Old World, members of this genus are called "
buzzard Buzzard is the common name of several species of birds of prey. ''Buteo'' species * Archer's buzzard (''Buteo archeri'') * Augur buzzard (''Buteo augur'') * Broad-winged hawk (''Buteo platypterus'') * Common buzzard (''Buteo buteo'') * Easte ...
s", but "
hawk Hawks are birds of prey of the family Accipitridae. They are very widely distributed and are found on all continents, except Antarctica. The subfamily Accipitrinae includes goshawks, sparrowhawks, sharp-shinned hawks, and others. This ...
" is used in the
New World The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas, and sometimes Oceania."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: ...
(Etymology: ''Buteo'' is the
Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
name of the
common buzzard The common buzzard (''Buteo buteo'') is a medium-to-large bird of prey which has a large range. It is a member of the genus '' Buteo'' in the family Accipitridae. The species lives in most of Europe and extends its breeding range across much of ...
). As both terms are ambiguous, buteo is sometimes used instead, for example, by the Peregrine Fund.


Characteristics

Buteos are fairly large birds. Total length can vary from and wingspan can range from . The lightest known species is the roadside hawk, at an average of although the lesser known white-rumped and
Ridgway's hawk Ridgway's hawk (''Buteo ridgwayi'') is a bird of prey in the family Accipitridae endemic to the island of Hispaniola (both Haiti and the Dominican Republic) in the Caribbean. It is classified as Critically Endangered because of habitat destructio ...
s are similarly small in average wingspan around , and average length around in standard measurements. The largest species in length and wingspan is the upland buzzard, which averages around in length and in wingspan. The upland is rivaled in weight and outsized in foot measurements and bill size by the
ferruginous hawk The ferruginous hawk (''Buteo regalis'') is a large bird of prey and belongs to the broad-winged buteo hawks. An old colloquial name is ferrugineous rough-leg, due to its similarity to the closely related rough-legged hawk (''B. lagopus''). The ...
. In both of these largest buteos, adults typically weigh over , and in mature females, can exceed a mass of .del Hoyo, J.; Elliot, A. & Sargatal, J. (editors). (1994). ''
Handbook of the Birds of the World The ''Handbook of the Birds of the World'' (HBW) is a multi-volume series produced by the Spanish publishing house Lynx Edicions in partnership with BirdLife International. It is the first handbook to cover every known living species of bird. ...
Volume 2'': New World Vultures to Guineafowl. Lynx Edicions.
''Eagles, Hawks and Falcons of the World'' by Leslie Brown & Dean Amadon. The Wellfleet Press (1986), .''CRC Handbook of Avian Body Masses'' by John B. Dunning Jr. (Editor). CRC Press (1992), . All buteos may be noted for their broad wings and sturdy builds. They frequently soar on thermals at midday over openings and are most frequently seen while doing this. The flight style varies based on the body type and wing shape and surface size. Some long-winged species, such as
rough-legged buzzard The rough-legged buzzard (Europe) or rough-legged hawk (North America) (''Buteo lagopus'') is a medium-large bird of prey. It is found in arctic and subarctic regions of North America, Europe, and Asia during the breeding season, and migrates s ...
s and
Swainson's hawk Swainson's hawk (''Buteo swainsoni'') is a large bird species in the Accipitriformes order. This species was named after William Swainson, a British naturalist. It is colloquially known as the grasshopper hawk or locust hawk, as it is very fond o ...
s, have a floppy, buoyant flight style, while others, such as
red-tailed hawk The red-tailed hawk (''Buteo jamaicensis'') is a bird of prey that breeds throughout most of North America, from the interior of Alaska and northern Canada to as far south as Panama and the West Indies. It is one of the most common members of ...
s and rufous-tailed hawks, tend to be relatively shorter-winged, soaring more slowly and flying with more labored, deeper flaps. Most small and some medium-sized species, such as,
red-shouldered hawk The red-shouldered hawk (''Buteo lineatus'') is a medium-sized buteo. Its breeding range spans eastern North America and along the coast of California and northern to northeastern-central Mexico. It is a permanent resident throughout most of its ...
, often fly with an alternation of soaring and flapping, thus may be reminiscent of an ''
Accipiter ''Accipiter'' () is a genus of birds of prey in the family Accipitridae. Some species are called sparrowhawks, but there are many sparrowhawks in other genera such as '' Tachyspiza''. These birds are slender with short, broad, rounded wings and ...
'' hawk in flight, but are still relatively larger-winged, shorter-tailed, and soar more extensively in open areas than ''Accipiter'' species do. Buteos inhabit a wide range of habitats across the world, but tend to prefer some access to both clearings, which provide ideal hunting grounds, and trees, which can provide nesting locations and security.


Diet

All ''Buteo'' species are to some extent opportunistic when it comes to hunting, and prey on almost any type of small animal as it becomes available to them. However, most have a strong preference for small
mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...
s, mostly
rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...
s. Rodents of almost every family in the world are somewhere preyed upon by ''Buteo'' species. Since many rodents are primarily nocturnal, most buteos mainly hunt rodents that may be partially active during the day, which can include
squirrel Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...
s and
chipmunk Chipmunks are small, striped rodents of subtribe Tamiina. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia. Taxonomy and systematics Chipmunks are classified as four genera: '' ...
s,
vole Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of lo ...
s, and
gerbil The Mongolian gerbil or Mongolian jird (''Meriones unguiculatus'') is a rodent belonging to the subfamily Gerbillinae. Their body size is typically , with a tail, and body weight , with adult males larger than females. The animal is used in s ...
s. More nocturnal varieties are hunted opportunistically and may be caught in the first or last few hours of light. Other smallish mammals, such as
shrew Shrews ( family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to dif ...
s, moles,
pika A pika ( , or ) is a small, mountain-dwelling mammal native to Asia and North America. With short limbs, a very round body, an even coat of fur, and no external tail, they resemble their close relative the rabbit, but with short, rounded ears. ...
s,
bat Bats are flying mammals of the order Chiroptera (). With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most birds, flying with their very long spread-out ...
s, and
weasel Weasels are mammals of the genus ''Mustela'' of the family Mustelidae. The genus ''Mustela'' includes the least weasels, polecats, stoats, ferrets, and European mink. Members of this genus are small, active predators, with long and slend ...
s, tend to be minor secondary prey, although can locally be significant for individual species. Larger mammals, such as
rabbit Rabbits are small mammals in the family Leporidae (which also includes the hares), which is in the order Lagomorpha (which also includes pikas). They are familiar throughout the world as a small herbivore, a prey animal, a domesticated ...
s,
hare Hares and jackrabbits are mammals belonging to the genus ''Lepus''. They are herbivores and live Solitary animal, solitarily or in pairs. They nest in slight depressions called forms, and their young are precociality, able to fend for themselves ...
s, and
marmot Marmots are large ground squirrels in the genus ''Marmota'', with 15 species living in Asia, Europe, and North America. These herbivores are active during the summer, when they can often be found in groups, but are not seen during the winter, w ...
s, including even adult specimens weighing as much as , may be hunted by the heaviest and strongest species, such as ferruginous, red-tailed and white-tailed hawks. Birds are taken occasionally, as well. Small to mid-sized birds, i.e.
passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped') which includes more than half of all bird species. Sometimes known as perching birds, passerines generally have an anisodactyl arrangement of their ...
s,
woodpecker Woodpeckers are part of the bird family (biology), family Picidae, which also includes the piculets, wrynecks and sapsuckers. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar and the extreme ...
s,
waterfowl Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which i ...
,
pigeon Columbidae is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with small heads, relatively short necks and slender bills that in some species feature fleshy ceres. ...
s, and gamebirds, are most often taken. However, since the adults of most smaller birds can successfully outmaneuver and evade buteos in flight, much avian prey is taken in the nestling or fledgling stages or adult birds if they are previously injured. An exception is the short-tailed hawk, which is a relatively small and agile species and is locally a small bird-hunting specialist. The
Hawaiian hawk The Hawaiian hawk or ''io'' (''Buteo solitarius'') is a raptor in the genus '' Buteo'' endemic to Hawaii, currently restricted to the Big Island. The ''io'' is one of two extant birds of prey that are native to Hawaii, the other being the '' pu ...
, which evolved on an isolated group of islands with no terrestrial mammals, was also initially a bird specialist, although today it preys mainly on introduced rodents. Other prey may include
snake Snakes are elongated limbless reptiles of the suborder Serpentes (). Cladistically squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales much like other members of the group. Many species of snakes have s ...
s,
lizard Lizard is the common name used for all Squamata, squamate reptiles other than snakes (and to a lesser extent amphisbaenians), encompassing over 7,000 species, ranging across all continents except Antarctica, as well as most Island#Oceanic isla ...
s,
frog A frog is any member of a diverse and largely semiaquatic group of short-bodied, tailless amphibian vertebrates composing the order (biology), order Anura (coming from the Ancient Greek , literally 'without tail'). Frog species with rough ski ...
s,
salamander Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All t ...
s,
fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...
, and even various
invertebrates Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordate subphylum ...
, especially
beetle Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...
s. In several ''Buteo'' species found in more tropical regions, such as the grey-lined hawk, reptiles and amphibians may come to locally dominate the diet.
Swainson's hawk Swainson's hawk (''Buteo swainsoni'') is a large bird species in the Accipitriformes order. This species was named after William Swainson, a British naturalist. It is colloquially known as the grasshopper hawk or locust hawk, as it is very fond o ...
, despite its somewhat large size, is something of exceptional
insect Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...
-feeding specialist and may rely almost fully on
crickets Crickets are orthopteran insects which are related to bush crickets and more distantly, to grasshoppers. In older literature, such as Imms,Imms AD, rev. Richards OW & Davies RG (1970) ''A General Textbook of Entomology'' 9th Ed. Methuen 886 ...
and
dragonflies A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of dragonflies are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threate ...
when wintering in southern
South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...
.
Carrion Carrion (), also known as a carcass, is the decaying flesh of dead animals. Overview Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures ...
is eaten occasionally by most species, but is almost always secondary to live prey. The importance of carrion in the Old World "buzzard" species is relatively higher since these often seem slower and less active predators than their equivalents in the
Americas The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a sing ...
. Most ''Buteo'' species seem to prefer to ambush prey by pouncing down to the ground directly from a perch. In a secondary approach, many spot prey from a great distance while soaring and circle down to the ground to snatch it.


Reproduction

''Buteo''s are typical accipitrids in most of their breeding behaviors. They all build their own nests, which are often constructed out of sticks and other materials they can carry. Nests are generally located in trees, which are generally selected based on large sizes and inaccessibility to climbing predators rather than by species. Most ''Buteo''s breed in stable pairs, which may mate for life or at least for several years even in migratory species in which pairs part ways during winter. Generally from 2 to 4 eggs are laid by the female and are mostly incubated by her, while the male mate provides food. Once the eggs hatch, the survival of the young is dependent upon how abundant appropriate food is and the security of the nesting location from potential nest predators and other (often human-induced) disturbances. As in many raptors, the nestlings hatch at intervals of a day or two and the older, strong siblings tend to have the best chances of survival, with the younger siblings often starving or being handled aggressively (and even killed) by their older siblings. The male generally does most of the hunting and the female broods, but the male may also do some brooding while the female hunts as well. Once the fledgling stage is reached, the female takes over much of the hunting. After a stage averaging a couple of weeks, the fledglings take the adults‘ increasing indifference to feeding them or occasional hostile behavior towards them as a cue to disperse on their own. Generally, young ''Buteo''s tend to disperse several miles away from their nesting grounds and wander for one to two years until they can court a mate and establish their own breeding range.


Distribution

The ''Buteo'' hawks include many of the most widely distributed, most common, and best-known raptors in the world. Examples include the
red-tailed hawk The red-tailed hawk (''Buteo jamaicensis'') is a bird of prey that breeds throughout most of North America, from the interior of Alaska and northern Canada to as far south as Panama and the West Indies. It is one of the most common members of ...
of
North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
and the
common buzzard The common buzzard (''Buteo buteo'') is a medium-to-large bird of prey which has a large range. It is a member of the genus '' Buteo'' in the family Accipitridae. The species lives in most of Europe and extends its breeding range across much of ...
of
Eurasia Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, Physical geography, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents d ...
. Most
Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined by humans as being in the same celestial sphere, celestial hemisphere relative to the invariable plane of the Solar ...
species are at least partially migratory. In
North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
, species such as broad-winged hawks and
Swainson's hawk Swainson's hawk (''Buteo swainsoni'') is a large bird species in the Accipitriformes order. This species was named after William Swainson, a British naturalist. It is colloquially known as the grasshopper hawk or locust hawk, as it is very fond o ...
s are known for their huge numbers (often called "kettles") while passing over major migratory flyways in the fall. Up to tens of thousands of these ''Buteo''s can be seen each day during the peak of their migration. Any of the prior mentioned common ''Buteo'' species may have total populations that exceed a million individuals. On the other hand, the Socotra buzzard and
Galapagos hawk The Galápagos hawk (''Buteo galapagoensis'') is a large hawk endemic to most of the Galápagos Islands. Description The Galapágos hawk is similar in size to the red-tailed hawk (''Buteo jamaicensis'') and the Swainson's hawk (''Buteo swains ...
s are considered vulnerable to extinction per the
IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...
. The
Ridgway's hawk Ridgway's hawk (''Buteo ridgwayi'') is a bird of prey in the family Accipitridae endemic to the island of Hispaniola (both Haiti and the Dominican Republic) in the Caribbean. It is classified as Critically Endangered because of habitat destructio ...
is even more direly threatened and is considered Critically Endangered. These insular forms are threatened primarily by
habitat destruction Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...
, prey reductions and poisoning. The latter reason is considered the main cause of a noted decline in the population of the more abundant
Swainson's hawk Swainson's hawk (''Buteo swainsoni'') is a large bird species in the Accipitriformes order. This species was named after William Swainson, a British naturalist. It is colloquially known as the grasshopper hawk or locust hawk, as it is very fond o ...
, due to insecticides being used in southern
South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...
, which the hawks ingest through crickets and then die from poisoning.


Taxonomy and systematics

The genus ''Buteo'' was erected by the French naturalist
Bernard Germain de Lacépède Bernard-Germain-Étienne de La Ville-sur-Illon, comte de Lacépède or La Cépède (; 26 December 17566 October 1825) was a French natural history, naturalist and an active freemason. He is known for his contribution to the Comte de Buffon's g ...
in 1799 by
tautonymy A tautonym is a scientific name of a species in which both parts of the name have the same spelling, such as ''Rattus rattus''. The first part of the name is the name of the genus and the second part is referred to as the ''specific epithet'' in ...
with the specific name of the common buzzard ''Falco buteo'' which had been introduced by
Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...
in 1758.


Extant species in taxonomic order


Fossil record

A number of
fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...
species have been discovered, mainly in North America. Some are placed here primarily based on considerations of
biogeography Biogeography is the study of the species distribution, distribution of species and ecosystems in geography, geographic space and through evolutionary history of life, geological time. Organisms and biological community (ecology), communities o ...
, ''Buteo'' being somewhat hard to distinguish from '' Geranoaetus'' based on
osteology Osteology () is the scientific study of bones, practiced by osteologists . A subdiscipline of anatomy, anthropology, archaeology and paleontology, osteology is the detailed study of the structure of bones, skeletal elements, teeth, microbone mo ...
alone:Wetmore (1933) * †'' Buteo dondasi'' (Late Pliocene of Buenos Aires, Argentina) * †'' Buteo fluviaticus'' (Brule Middle? Oligocene of Wealt County, US) – possibly same as ''B. grangeri'' * †'' Buteo grangeri'' (Brule Middle? Oligocene of Washabaugh County, South Dakota, US) * †'' Buteo antecursor'' (Brule Late? Oligocene) * †?''Buteo'' ''sp.'' (Brule Late Oligocene of Washington County, US) * †'' Buteo ales'' (Agate Fossil Beds Early Miocene of Sioux County, US) – formerly in '' Geranospiza'' or '' Geranoaetus'' * †'' Buteo typhoius'' (Olcott Early ?- snake Creek Late Miocene of Sioux County, US) * †'' Buteo pusillus'' (Middle Miocene of Grive-Saint-Alban, France) * †''Buteo'' ''sp.'' (Middle Miocene of Grive-Saint-Alban, France – Early Pleistocene of Bacton, England) * †'' Buteo contortus'' (snake Creek Late Miocene of Sioux County, US) – formerly in ''Geranoaetus'' * †'' Buteo spassovi'' (Late Miocene of Chadžidimovo, Bulgaria) * †'' Buteo conterminus'' (snake Creek Late Miocene/Early Pliocene of Sioux County, US) – formerly in ''Geranoaetus'' * †''Buteo'' ''sp.'' (Late Miocene/Early Pliocene of Lee Creek Mine, North Carolina, US) * †'' Buteo sanya'' (Late Pleistocene of Luobidang Cave, Hainan, China) *''† Buteo chimborazoensis'' (Late Pleistocene of Ecuador) *†'' Buteo sanfelipensis'' (Late Pleistocene, Cuba) An unidentifiable accipitrid that occurred on
Ibiza Ibiza (; ; ; #Names and pronunciation, see below) or Iviza is a Spanish island in the Mediterranean Sea off the eastern coast of the Iberian Peninsula. It is 150 kilometres (93 miles) from the city of Valencia. It is the third largest of th ...
in the
Late Pliocene Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * Late (The 77s album), ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudo ...
/
Early Pleistocene The Early Pleistocene is an unofficial epoch (geology), sub-epoch in the international geologic timescale in chronostratigraphy, representing the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently esti ...
may also have been a ''Buteo''.Alcover (1989) If this is so, the bird can be expected to aid in untangling the complicated
evolution Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...
ary history of the
common buzzard The common buzzard (''Buteo buteo'') is a medium-to-large bird of prey which has a large range. It is a member of the genus '' Buteo'' in the family Accipitridae. The species lives in most of Europe and extends its breeding range across much of ...
group. The prehistoric species ''"Aquila" danana'', '' Buteogallus fragilis'' ( Fragile eagle), and '' Spizaetus grinnelli'' were at one time also placed in ''Buteo''.


Notes


References


Further reading

* "Raptors of the World" by Ferguson-Lees, Christie, Franklin, Mead & Burton. Houghton Mifflin (2001), . * Alcover, Josep Antoni (1989): Les Aus fòssils de la Cova de Ca Na Reia. ''Endins'' 14-15: 95-100. n Catalan with English abstract* Ballmann, Peter (1969): Les Oiseaux miocènes de la Grive-Saint-Alban (Isère) he Miocene birds of Grive-Saint-Alban (Isère) ''
Geobios Geobios is an academic journal published bimonthly by the publishing house Elsevier. Geobios is an international journal of paleontology, focusing on the areas of palaeobiology, palaeoecology, palaeobiogeography, stratigraphy and biogeochemistry ...
'' 2: 157–204. rench with English abstract (HTML abstract) * Brodkorb, Pierce (1964): Catalogue of Fossil Birds: Part 2 (Anseriformes through Galliformes). ''Bulletin of the Florida State Museum'' 8(3): 195–335
PDF or JPEG fulltext
* Cracraft, Joel (1969): Notes on fossil hawks (Accipitridae). ''
Auk Auks or alcids are birds of the family Alcidae in the order Charadriiformes. The alcid family includes the Uria, murres, guillemots, Aethia, auklets, puffins, and Brachyramphus, murrelets. The family contains 25 extant or recently extinct speci ...
'' 86(2): 353–354
PDF fulltext
* Mlíkovský, Jirí (2002): ''Cenozoic Birds of the World, Part 1: Europe''. Ninox Press, Prague. PDF fulltext
!-- This should be treated with extreme caution as regards merging of species. Splits are usually good though. See also critical review in Auk121:623-627 here http://www.findarticles.com/p/articles/mi_qa3793/is_200404/ai_n9396879 --> * Wetmore, Alexander (1933): Status of the Genus ''Geranoaëtus''. ''
Auk Auks or alcids are birds of the family Alcidae in the order Charadriiformes. The alcid family includes the Uria, murres, guillemots, Aethia, auklets, puffins, and Brachyramphus, murrelets. The family contains 25 extant or recently extinct speci ...
'' 50(2): 212
DjVu fulltextPDF fulltext
{{Authority control Bird genera Extant Oligocene first appearances Taxa named by Bernard Germain de Lacépède